1. Field of the Invention
The present invention relates to clamping devices used to secure opposing objects to one another and more particularly to a clamping device capable of securing opposing objects to one another at nearly any desired angular relationship with respect to one another, while applying substantially even pressure at the joint formed between the objects.
2. Description of the Prior Art
Clamping devices are frequently used by woodworkers when joining opposing objects to one another with glue and/or fasteners. Numerous different clamp designs are known for securing objects in an edge-to-edge, coplanar fashion. However, these clamps and the method of using the same are typically only useful when the mating faces of the opposing objects are disposed at right angles. Cabinet making and other woodworking endeavors frequently require the joining of opposing objects at an angle with respect to one another. One common example can be found in the ubiquitous picture frame, where opposing pieces of wood are joined at ninety degree angles with respect to one another at mating faces that have each been cut at a forty-five degree angle. Clearly, the basic clamp design that provides linear clamping pressure will not work to secure the mitered pieces of wood to one another at the angled joint.
Several prior art designs exist for clamping opposing pieces of wood to one another at an angle. For example, U.S. Pat. No. 1,169,671 discloses a clamping device for securing objects at ninety degree angles with respect to one another. Specifically, the clamp provides a pair of jaw members set at a ninety degree relationship to one another. One jaw is disposed in a fixed position, while the opposing jaw may be manually actuated toward and away from the first jaw. While such a design is helpful, it has a number of shortcomings. First, the angular relationship of the jaws is set for securing objects at right angles to one another. Acute or obtuse angles are not obtainable using this design. Secondly, the angular disposition of the jaws provides unequal clamping pressure on the joint, which limits the amount of pressure that may be applied to the joint and may ultimately weaken the same. U.S. Pat. No. 5,785,305 functions in a similar manner, having a first clamping arm fixed in a static position and angle with respect to the horizontal. A second clamping arm is fixed in its angular relationship to the horizontal and is manually advanced and retracted with respect to the first clamping arm. This design also fails to provide a variable angle function. Moreover, despite the fact that the clamping pressure provided at the mating surfaces of the opposing objects is more even than that provided by predecessor clamps, it still fails to provide substantially uniform pressure along the mating surfaces.
U.S. Pat. No. 2,941,557 discloses an adjustable angle clamp that can secure opposing structures in a plurality of different angles with respect to one another. The clamp is designed to have a pair of opposing clamping surfaces that are pivotably coupled to one another and a pair of clamping arms that are disposed perpendicularly to the clamping surfaces to secure the objects thereto. While such a design provides an adjustable angle feature, it fails to provide a clamp that is capable of applying clamping pressure at the joint formed between the opposing objects. Moreover, the manner in which the opposing objects are secured within the clamp requires awkward, minute adjustments to the position of each of the opposing pieces of wood in order to properly align their mating surfaces at the set angle.
Accordingly, what is needed is a novel clamping device that is capable of securing opposing objects to one another at various angles with respect to one another while providing a substantially even claming force at the joint formed between the opposing objects.